Dehydrated mashed potato mix, which is now widely available, need only be mixed with hot water for preparation of ready-to-serve mashed potatoes. From the standpoint of appearance, taste and texture the reconstituted product is practically indistinguishable from mashed fresh potatoes, and the dehydrated mixes, by conserving labor and storage space, offer very substantial savings to restaurants, catering organizations and institutions.
For maximum economy, servings of reconstituted mashed potato mix should be prepared as and when they are needed, so that every portion will be hot and fresh and none of the dehydrated material will be wasted. However, manual mixing of individual servings or small batches is obviously impractical and inefficient, and heretofore no mixer has been available that could quickly mix and dispense single portions of the reconstituted product.
Attempts have been made to employ hot beverage dispensers for reconstituting and dispensing mashed potato mix, and at first the use of such machines seemed very promising, but after a time it was found that they were not suitable for the purpose. In a beverage dispenser for whipped hot chocolate, for example, metered quantities of hot water and chocolate mix powder are run into a funnel-like hopper from which they fall into the top of a mixing chamber wherein a small centrifuging agitator rotates at high speed. The agitator thoroughly mixes the hot water and dry material and whips air into the mixture. The mixture leaves the mixing chamber through an outlet in its bottom and passes into a downwardly projecting spout that guides it into a cup or the like.
The mixed beverages dispensed by machines of the type just described are essentially liquids that flow very freely and have a little tendency to settle on the surfaces of the mixing chamber and the ducts that extend downwardly to and from it. By contrast, reconstituted mashed potato mix, when ready to serve, is so thick and viscous that it flows only in response to rather substantial force or pressure, and it is sticky enough to leave deposits even on a surface as smooth as that of a glazed china plate.
Notwithstanding these important differences between the mixed products, it appeared during the initial attempts to employ hot beverage dispensers for reconstituting mashed potato mix that satisfactory operation could be obtained by merely reducing the input of hot water in proportion to the rate at which dry material was fed into the mixing chamber. A hot beverage machine so adjusted could very quickly dispense several servings of mashed potatoes with no apparent difficulty. After prolonged operation, however, a point was usually reached at which the machine became plugged with mashed potatoes and stopped dispensing.
Investigation disclosed that this peculiarly unreliable behavior of the beverage machine was due to the manner in which dehydrated mashed potato material combines with water. When initially mixed with water, the dehydrated material forms a slurry that flows very freely. Within a very few seconds, however, the individual particles of the mix absorb sufficient water to swell and combine into a substantially non-flowing mass. It was found that in the conventional beverage dispenser most of the particles of dehydrated material passed through the machine during the critical period of four or five seconds before congealing took place, but a certain amount of material remained in the mixing chamber for a longer time and formed a deposit on its inner surface. As this deposit built up, increasing proportions of the material were retained in the mixing chamber too long, and the build-up of deposited material accelerated to the point where the inlet or the outlet of the mixing chamber, or both, were plugged with mashed potato.
After the mechanics of the plugging process had been discovered, it was evident that a successful machine for reconstituting and dispensing mashed potato mix had to be so arranged that none of the mix material would be retained in the mixing chamber for more than about three seconds. But it was by no means obvious how a machine could be designed to ensure the attainment of that objective, especially in view of other and equally important requirements that must be met.
For complete success, mixing of the dehydrated potato material with water must not only be fast but thorough. The particles of mix material should be distributed fairly uniformly through the water, and any clumps or clusters of particles should be broken up and dispersed so that every surface of every particle is exposed to the water. In addition, air should be whipped into the mixture as it is being formed, so that the dispensed product will be light and fluffy.
These mixing requirements should be met in apparatus that is simple, inexpensive and sanitary. There should be no surfaces along the path of the mix material that are not readily accessible for cleaning, and preferably all parts of the machine that are exposed to wet or moistened mix particles should be capable of being thoroughly cleaned by flushing or rinsing. Obviously the machine should be compact, attractive in appearance, and require a minimum of power for its operation. Low cost is another obvious imperative, and for its attainment the machine should incorporate as many components as possible that are standard with other types of mixing and dispensing equipment.
The general object of the present invention is to provide a mixing machine which is capable of reconstituting and dispensing dehydrated mashed potato material and which fully and satisfactorily meets all of the above-stated requirements and desiderata.
Thus it is also a general object of this invention to provide a machine that is capable of mixing dehydrated mashed potato mix with hot water and reliably dispensing one or several portions of fluffy, appealing mashed potatoes within a very few seconds.
Another general object of the invention is to provide a machine that enables restaurants and food service institutions to achieve optimum economy in the use of dehydrated mashed potato mix by effecting practically instant reconstitution of such material when it is required and in exactly the quantities in which it is required.
A more specific object of this invention is to provide a mixing and dispensing machine that can be used--with minor and easily made adjustments--with dry hot chocolate mix as well as with mashed potato mix.
A further specific object of the invention is to provide a mixing and dispensing machine of the above described character wherein most of the parts are standard components of widely available commercial beverage dispensing machines, to afford maximum economy in both the manufacture and the repair of machines of this invention.
With these observations and objectives in mind, the manner in which the invention achieves its purpose will be appreciated from the following description and the accompanying drawing, which exemplify the invention, it being understood that changes may be made in the specific apparatus disclosed herein without departing from the essentials of the invention set forth in the appended claims.